I believe that the Su 30 intakes are sufficient to accommodate more powerful engines. In fact Russians are already upgrading their Su 30 SM ( Russian version of Su 30 MKI ) to SM2 standard ( proposed Super Sukhoi upgrade for MKI )
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The Super Sukhoi Su-30SM2
The upgraded version of the Su-30SM will not only have improved combat features but will also use various parts and equipment from the Su-35. As a result, the maintenance of a large fleet of both types of modern fighters will be simplified. This is especially important in relation to engines, the most expensive aircraft components.
The Su-30SM2 will receive the AL-41F-1S engine, which is also used in the Su-35S. Compared to the power plant used so far in the Su-30SM, its thrust will increase by more than 16%, to 14,500 kg at full post-combustion. In addition, it reduces the cost of maintenance, by doubling the interval between revisions, now reaching 4 thousand hours. Other improvements and plasma ignition made it more efficient, reducing its fuel consumption.
Su-30SM2
Changes to onboard electronics and software will allow the use of new missiles and bombs designed to arm the Su-35 and the fifth-generation Su-57 stealth fighter.
Other improvements include a new radar, the Irbis-E, a powerful PESA-type radar also inherited from the Su-35. It will allow the Su-30SM2 to detect ground and air targets from a greater distance, with certain anti-stealth capabilities. It will also allow the fighter to use the latest long-range missiles.
The Su-30SM2s will receive the latest integrated multi-channel communication, data exchange, navigation, and identification (OSNOD) system, developed for the Su-57 and to be installed on all combat aircraft. Among its advantages, it allows aircraft and drones to communicate with each other, maintain high-speed contact with ground control points, and integrate into modern combat networks.”